Section 6 2 TRƯỜNG ĐIỆN TỪ

Introduction to Electromagnetic Fields,to supplement “Elements of Engineering Electromagnetics, Sixth Edition” by Nannapaneni Narayana Rao Edward C.. Jordan Professor of Electrical and

Introduction to Electromagnetic Fields,

to supplement “Elements of Engineering

Electromagnetics, Sixth Edition”

by

Nannapaneni Narayana Rao

Edward C Jordan Professor of Electrical and Computer Engineering

University of Illinois at Urbana-Champaign, Urbana, Illinois, USA

Distinguished Amrita Professor of Engineering Amrita Vishwa Vidyapeetham, Coimbatore, Tamil Nadu, India

6.2 Line Terminated

by Resistive Load

V V

V0 t = 0 Z0, v p

z = 0 z

 Semi-infinite Line, No Source Resistance

p p

0 for

p p

p p p p p p

z = 150 m

I, A

0.5 0

Effect of Source Resistance

z = 0

– + +

Define Voltage Reflection Coefficient,

Then, Current Reflection Coefficient

R S R S g

11

+ –

(+) (–)

For constant voltage source,

Actual Situation in the Steady State

One (+) Wave and One (–) Wave

ISS  V0

R L  R g , VSS 

V0 R L

R L  R g

V SS  V SS – V 0 – R g ISS  ISS–  B.C at z 0

V SS  V SS R– LISS  ISS–  B.C at z l

I SS V

 SS

Z0 () wave

I SS– – V

– SS

Z0 (–) wave

Four equations for the four unknowns

V SS , V SS ,– I SS , I SS–

+ –

Bounce Diagram Technique:

Constant Voltage Source

0 80

224 3

1124 15

z

S – 1

141 225

9

45

2 3

z

–S 1

0 80

224 3

1 3 5

0

141 225

9

45

2 3

I, A

1

0 2 4 6 8

141 225 9

15

t, s

t, s

V, V z = l

224 3

2 3

t, s

t,  s

Rectangular Pulse Source

0 2 4

1 3

z = 0 z = l

2 4

0

3

80 0

60 0 16 0 16 15

–

–60 –4 4 4/15

20 –20

20

–4/3 4/3

–4 4 3 –

60 V

16 3